The series features Craig Stirling, Sharron Macready and Richard Barrett as agents for a United Nations law enforcement organization called "Nemesis", based in Geneva. Barrett is a code breaker, Stirling a pilot, and Macready a recently widowed scientist and doctor.

During their first mission as a team, their plane crashes in the Himalayas. They are rescued by an advanced civilization living secretly in the mountains of Tibet, who save their lives, granting them perfected human abilities, including powers to communicate with one another over distances by ESP (telepathy), to foresee events (precognition), enhanced five senses and intellect and physical abilities to the fullest extent of human capabilities.[2][3]

Many stories feature unusual villains, such as fascist regimes from unspecified South American countries, Nazis (a common theme of ITC 1960s and '70s TV, in part due to both the domestic audience and writers having been the war generation) or the Chinese. The villains' schemes often threaten world peace – Nemesis's brief is international, so the agents deal with threats transcending national interests. The main characters have to learn the use of their new powers as they go along, keeping what they discover secret from friends and foe alike. Each episode begins with an advert, followed by the title/theme song. Immediately following that is a post-title sequence vignette in which one of The Champions demonstrates exceptional mental or physical abilities, often astonishing or humiliating others. In one example Stirling participates in a sharpshooting contest. Stirling hears the ticking of his girlfriend's lost wristwatch in a large field and finds it. In another, Macready's car is blocked in, two laughing passing drunks try to lift it out but she goes round to the other side and pulls it out of the parking space one-handed. Paradoxically, the narration during these often public demonstrations usually mentions the need to keep the powers a secret.

The only other series regular is the Champions' boss, Tremayne. He does not know that his agents have special abilities, although he does ask innocent questions about just how on their missions they managed to carry out certain tasks about which their reports were vague.

The series was created by Dennis Spooner and its episodes were written by veterans of popular British spy series, including The Avengers and Danger Man. The series used an unfilmed script written for Danger Man.

Because of budget constraints, many sets were reused: three episodes were set on a submarine and three in the Arctic. Stock footage was used. Like most such ITC series much of the exterior action took place in and around the studio lot – usually, as was the case with The Champions, Elstree Studios in Borehamwood, Herts. For at least one episode, Desert Journey, foreign filming did take place, but with a second unit, and extras standing in for the main cast.

Although short-lived, the series had three repeat runs across the ITV regions up to 1976 and once more on ITV in September–October 1984. It was also regularly repeated in the UK, on ITV's digital channel ITV4 until January 2011 (making The Saint, the remaining ITC property to premiere on ITV4).[4]The Champions was broadcast on BBC2 in 1995, at about the time when Gaunt was appearing in the sitcom Next of Kin and it had at least three further repeat runs after that.

Episodes were released on DVD in North America,[5] and in the UK, where the full series has been released twice, with the most recent edition seeing Damon, Bastedo and Gaunt reunite to provide a commentary for several episodes (Damon's continuing role on US series General Hospital meant that Bastedo and Gaunt had to be flown to America for this to occur).[6][7]

The series was shown in Italy in the early 80s in syndication under the title Tris d'Assi (that means in English Three Aces) and more recently (90s) on Canal Jimmy (Sky), but an Italian DVD collection has never been released because in that country The Champions is an almost completely forgotten show, remembered only by few loyal fans.

In 2010 company Network DVD re-released The Champions: The Complete Series'' as a complete DVD Region 2 box set of all episodes on 9 discs (including the rare 'bookends' version of the first episode). (Also they released the music from the series on 3 CDs.) [8]

In 1983, ITC edited episodes "The Beginning" and "The Interrogation" into Legend of the Champions, a feature-length film intended for overseas markets.[7]

Unusually for such features, the two episodes were not simply joined together, but substantially re-cut and edited, with "The Interrogation" being the framing episode, and the flashback sequences originally used in that episode (principally from "The Beginning") expanded. Additionally, new credits were filmed, not using any of the original actors but photographs taken at the time.

A notable plot change was the renaming of a character from the original version of "The Beginning" to accommodate a plot device in "The Interrogation". In "The Interrogation", Craig Stirling is ostensibly being quizzed on the activities of one Julius Retford, who remains unseen. For the film, the opening credits explicitly identify Retford as the character named Ho Ling (played by Ric Young) in "The Beginning". This allows the germ warfare theme of "The Beginning" to interlink with the sequences in "The Interrogation". Confusingly, in the end credits Young is credited as playing 'Ho Ling', a name never used in the film version.

This release credited Stuart Damon as the star, with Alexandra Bastedo and William Gaunt receiving co-star credits. This was partly because Damon was a well-established star in the US by this time, and partly because "The Interrogation" is essentially a two-hander between Damon and Colin Blakely, with the rest of the regular cast appearing only briefly.

Legend of the Champions was released on DVD as part of the Network box-set.

Note: 'Bookend' sequences were shot for the first episode "The Beginning" showing Richard Barrett (William Gaunt) recording the story on to a tape recorder in Tremayne's office, this was done so that the episode could be shown out of order on repeat runs without causing any continuity problems, both sequences were included as extras on the Network DVD box-set.

The three Nemesis agents recover from a plane crash in the Tibetan mountains to find their injuries healed. In the course of the episode, they learn they have new abilities bestowed on them by their rescuers, people from an ancient civilisation, and have to evade capture from the Chinese military.

Sharron is sent undercover to a training establishment in which a scientist is using new techniques to produce agents who have the same level of abilities as the Champions. Nemesis is interested in the organisation because one of its graduates has tried to break into a military establishment and steal secrets.

The trio are sent to investigate the possibility that caches of guns have been left in Austria by the SS and end up discovering a secret Nazi hide out in the local iron mines, complete with surviving Nazis who think World War II is still going on.

This was one of the more comedic episodes. The trio are detailed to guard the former dictator of a small South American country, La Revada, who is living in exile in the South of France. This is because some of his political opponents are planning to assassinate him, which would destabilise the political situation in the region. El Caudillo (as the former dictator insists on being called) turns out to be a vainglorious, not very intelligent womaniser who likes to prove that he is superior to everyone around him. However, the trio, who are posing as members of his household staff (Barrett as a chef, Macready as a secretary and Stirling as his head of security) manage to save him from the assassins, though their cover is blown in the process and they are revealed as agents of Nemesis.

The Champions are sent to investigate a tropical island where visitors have a history of disappearing. Coming on shore in two parties, they discover and thwart an international conspiracy to threaten world peace.

The Champions are assigned to escort an Eastern European head of state, Dubrovnik, on his visit to Britain. During a dive in a Scottish loch, their submarine is sabotaged and Dubrovnik is injured. Richard and Sharron are forced to face down a mutiny within the crew, who want to surface and save their lives; the submarine cannot be allowed to surface if Dubrovnik is to survive the surgery, which Sharron has performed. Once Dubrovnik is out of danger, Craig conveys instructions to Richard and Sharron on how to work the submarine via the scrambled phone link, which with their abilities, they can decipher.

After burglars break into Nemesis headquarters to access information on Richard, Craig is assigned to monitor him. Richard, however, allows himself to be abducted, leaving a message for his colleague. He finds himself imprisoned in a luxurious room (the "gilded cage" of the title), where his captor (John Carson) threatens him that, unless Richard can decipher a code, a young woman, Samantha (Jennie Linden), will be killed.

While on holiday in Haiti Sharron investigates a plot to brainwash important figures in the worlds of politics, science and business, apparently orchestrated by a local sorcerer, Damballa. Richard and Craig become involved later, only to discover that Sharron has apparently been discovered by the plotters and brainwashed herself.

The trio are sent to investigate when several Interpol agents commit motiveless suicide. They discover that an Italian American gangster forms the only connection between the agents and set up a sting in which Craig threatens him, so as to discover his methodology. This proves almost too successful when Craig is slipped the "suicide drug" responsible and the others have to race against time to find him before he kills himself.

Craig is captured after a mission in Hong Kong, and held in a cell where he is subject to interrogation by various cruel means. The unnamed interrogator (Colin Blakely) wants information about Craig's last mission. Despite nearing breaking point, Craig escapes the room, only to find he is at Nemesis headquarters; the interrogator is a member of Nemesis internal security, charged with finding out how Craig completed his last mission (his report had been less than clear at certain points, which were where his powers had come into play). Tremayne halts the investigation over the interrogator's protests, but the episode ends with Craig expressing bitterness towards his colleagues for their failure to intervene. All of the three are unhappy with Tremayne due to his part in the interrogation as well.

This episode was unusual for featuring only one extra set (though it included flashbacks to earlier episodes) and for focusing mostly on one character. The last episode in the syndication package, it was intended to be the season finale; the characters are left with little if any mutual trust, which is not reflected in any other episodes.

The trio investigate an operation run by an ex-Nazi doctor who is providing plastic surgery, and hence future anonymity, for international criminals. Craig and Sharron go undercover as an Italian gangster and his moll but Richard is forced to move in and masquerade as a vagrant, in order to provide a matching blood group for them (because vagrants provide the raw biological material for the operation).

Barrett, tipped off by a journalist contact, investigates a project in the Welsh countryside which is experimenting with freezing people at the point of death so that they can be revived once medical technology is advanced enough to help them. Luckily for him (since he is captured by the people running the project and placed in cryogenic storage himself before he manages to escape) Craig and Sharron have been placed on his trail by Tremayne and help him to close the project down.

The agents rescue an eminent female scientist who has returned to her home country and been detained against her will by the dictatorship, which runs it. The government want her to do her work there, in order to gain reflected prestige from her medical discoveries. This episode featured a performance from Philip Madoc, as the scientist's sleazy estranged husband, and a sequence where Stirling and Barrett rescue the scientist from a blacked out police station (not a problem for them, as they can see in the dark).

The agents are sent to investigate the disappearance of several eminent scientists - the only link is that all of them have theoretically been seconded to a non-existent "Project Zero". Richard goes undercover as an electronics expert and makes it to the underground base, but is discovered and has to pose as a journalist looking for a story. Craig and Sharron are forced to follow him in. Once they get to the base they free Richard, who has been fitted with an explosive collar, and lead the scientists in an attack on the control room. However, they do not succeed in catching the people running the base and they escape with the super weapon the scientists have been developing. However, Sharron, who escaped earlier to get help, has sabotaged the weapon and the villains are destroyed when it explodes and vaporises their plane as they attempt to destroy the base.

In order to restore stability to a small Middle Eastern principality, the agents kidnap the son of the former Bey (played by Jeremy Brett), who is leading a dissolute life as an exile in Rome. Craig and Sharron fly him into the area but are forced to land due to a sand storm and have to cross the desert (the "journey" of the title) to get him to his destination. Meanwhile Richard deals with the politicians in the principality, though it is Craig who saves the new Bey's life when an assassination attempt is made. This episode features Roger Delgado in a role as the Prime Minister/Vizier of the principality.

A spy is captured at a foreign embassy but manages to dispose of the film, hiding what he was doing there. Craig is placed undercover as his cellmate so that he can arrange an escape, take the man with him, and find out who is employing him.

After a senior figure in British Intelligence is brainwashed into breaking in to his own secure vault (located underneath a tailor's shop) the Champions are sent to test its security and find out what happened.

This was one of the few episodes that did not feature two stories running side by side. The three agents work on bringing a gunrunner to justice and recovering a consignment of World War 2 Japanese rifles.

Barka (Eric Pohlmann) is using a lethal hallucinogenic drug to brainwash Nemesis agents and use them as assassins. Tremayne is his latest target, leading Craig, Richard and Sharron to work against time to find an antidote. During the course of their investigations, Richard is captured by Barka and subjected to the same treatment; the target he is given to eliminate is Craig. Although Richard's colleagues track down the villains and seize a sample of the drug from which an antidote can be created, the ensuing fight between them and Richard teaches Craig "a lesson in equality".

^"ITC". screenonline. British Film Institute. Retrieved 2007-11-10. The cast had taken their screen tests in December 1966 and filming had begun in February 1967 in color three years before that became the standard in the U.K.